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Do multiple cycles of aeolian deposit-pedogenesis exist in the reticulate red clay sections in southern China?

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Chinese Science Bulletin 2003年第2期48卷 1251-1258页

作者： xuefeng hu Tianfan Cheng Hexin Wu Shanghai Univ Dept Environm Sci & Engn Shanghai 200072 Peoples R China

The Xiangyang reticulate red clay section was newly sampled in high-resolution. The viewpoints different from the previous studies[17] are put forward after studying Munsell color values, weathering degrees, magnetic parame-ters and stable carbon isotopic compositions of the section. They are as follows: (1) The curves of hue, DCB extracted iron (Fed), DCB extracted iron/total iron ratio (Fed/Fet), weathering index (BA) of the section show that the redness is not significantly correlated with the weathering degree of the layers though the uppermost yellow-brown-colored layer is relatively weakly weathered. The variation in hues of the section is possibly attributed to the change of hematite and goethite contents. It is insufficient to determine the existence of the multiple deposit-pedogenesis cycles in the section, like the loess-paleosol sequence in Chinese Loess Plateau, only by the color variation. (2) Magnetic susceptibility (c) values in the non-reticulate and weakly reticulate layers are high; but are quite low in the reticulate red clay layer. The former are more than ten times higher than the latter because of the leaching and collapse of superparamagnetic (SP) and stable single domain (SSD) magnetic particles during the plinthitic processes. Hence, c values in the section are not controlled by weathering and pedogenic processes, and no longer have clear paleoclimatic implication. It is not correct to prove the existence of the multiple deposit-pedogenesis cycles in the section using c curves. (3) The organic d 13C curve of the section illustrates the reduction of forests and increasing of C4 plants in the study area since the late stage of the Qua-ternary period. It could not prove the existence of the multi-ple deposit-pedogenesis cycles in the section either. (4) As a matter of fact, it is difficult to prove the existence of the mul-tiple deposit-pedogenesis cycles in the Xiangyang section like the loess-paleosol sequence in Chinese Loess Plateau using t

关键词： reticulate red clay Xianyyang reticulate red clay section (Xiangyang section) c weathering degree.

Could the Stock Market Adjust Itself? An Empirical Study Based on Mean Reversion Theory

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Journal of Systems Science and Information 2020年第2期11卷 97-115页

作者： Shuangjie LI xuefeng hu Liming WANG School of Economics and Management Beijing University of TechnologyBeijing 100124China UCD Irish Institute for Chinese Studies University College DubinUCD BelfieldDublin 4Ireland

This paper mainly studies whether and how stock prices fluctuate around their intrinsic *** on data from 10 stock markets for the period between 2000 and 2018,we demonstrate that the relative price fluctuates around and approaches the intrinsic value in the long *** the ten markets,the relative price crosses the intrinsic value on average once in 3~4 *** growth is a key factor in rising stock prices,but the level of valuations in the market has a regulatory effect to the growth of price in the future:For every 1%increase in valuation,the price tends to decline by 0.26%in the next year,0.74%in the next 3 years.

关键词： stock market mean reversion valuation ratio adjustment mechanism trend forecast

A Novel Soft-start Method for SVG Based on D-axis Orientation

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Chinese Journal of Electrical Engineering 2021年第1期7卷 55-62页

作者： Shicheng Zheng Ying Shu Mengmeng Qi Jiahong Lang xuefeng hu School of Electrical and Information Engineering Anhui University of TechnologyMa’anshan 243002China Key Lab of Power Electronics&Motion Control Anhui University of TechnologyMa’anshan 243002China

In this paper,a novel method for shock-free soft-start is *** novel method can realize the aim of no-overshoot and inrush of current during the entire soft-start process,thus the start process is safe,stable,and *** the uncontrolled rectification stage ends,a sinusoidal signal synchronized with the grid voltage is generated through dq coordinate transformation and D-axis orientation,then the signal is transmitted to the three-phase inverter *** AC voltage output of the inverter bridge is superimposed on both ends of the soft-start resistor along with the *** open-loop control method is adopted to gradually reduce the modulation ratio of the sinusoidal PWM wave until the capacitor voltage on the DC side reaches the rated voltage value,then the soft-start resistor is removed,which means the shock-free soft-start process is *** results prove the effectiveness and feasibility of the control strategy proposed in this paper.

关键词： Soft-start coordinate transformation modulation ratio shock-free D-axis orientation

Micro‐mechanism study on synergistic degradation of the oil‐paper insulation with dibenzyl disulfide,hexadecyl mercaptan and benzothiophene

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High Voltage 2021年第3期6卷 448-459页

作者： Haoxi Cong Hao Pan xuefeng hu Minhao Zhang Qingmin Li School of Electrical and Electronic Engineering North China Electric Power UniversityBeijingChina State Key Laboratory of Alternate Electrical Power System with Renewable Energy Sources North China Electric Power UniversityBeijingChina

In recent years,there have been many cases of transformer failures caused by corrosive *** present,research mainly focuses on the single sulfide dibenzyl disulphide,but few research on multiple sulphur or the oil‐paper hybrid *** this study,three typical sulfides dibenzyl disulfide,hexadecyl mercaptan and benzothiophene were selected to form seven sulfide‐oil‐paper *** relaxation calculations were carried out,and through molecular dynamics simulation,the synergistic effect of different sulfides on the properties of insulating paper and insulating oil was *** show that the coexistence of the three sulfides has the most severe weakening on the mechanical properties of cellulose,and it also causes great damage to hydrogen *** mercaptan has a weaker effect on hydrogen bond destruction,but it will greatly aggravate the cellulose chain *** viscosity of insulating oil is generally increased by the influence of *** mercaptan is the main factor affecting the *** has little effect on the viscosity,ctive protection technology on sulphur corrosion.

关键词： corrosion sulfide sulphur

FGF8-mediated signaling regulates tooth developmental pace during odontogenesis

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Journal of Genetics and Genomics 2022年第1期49卷 40-53页

作者： Chensheng Lin Ningsheng Ruan Linjun Li Yibin Chen Xiaoxiao hu YiPing Chen xuefeng hu Yanding Zhang Fujian Key Laboratory of Developmental and Neural Biology and Southern Center for Biomedical Research College of Life SciencesFujian Normal UniversityFuzhouFujian 350117China Department of Cell and Molecular Biology Tulane UniversityNew OrleansLA 70118USA

The developing human and mouse teeth constitute an ideal model system to study the regulatory mechanism underlying organ growth control since their teeth share highly conserved and well-characterized developmental processes, and their developmental tempo varies notably. In the current study, we manipulated heterogenous recombination between human and mouse dental tissues and demonstrated that the dental mesenchyme dominates the tooth developmental tempo and FGF8 could be a critical player during this developmental process. Forced activation of FGF8 signaling in the dental mesenchyme of mice promoted cell proliferation, prevented cell apoptosis via p38 and perhaps PI3 K-Akt intracellular signaling,and impelled the transition of the cell cycle from G1-to S-phase in the tooth germ, resulting in the slowdown of the tooth developmental pace. Our results provide compelling evidence that extrinsic signals can profoundly affect tooth developmental tempo, and the dental mesenchymal FGF8 could be a pivotal factor in controlling the developmental pace in a non-cell-autonomous manner during mammalian odontogenesis.

关键词： FGF8 Tooth Developmental pace Non-cell-autonomous

High-Voltage-Gain DC-DC Converter with Three-Winding Coupled Inductor

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Chinese Journal of Electrical Engineering 2019年第1期5卷 10-23页

作者： Wenjuan Liang xuefeng hu Hao Chen Guiyang Wu Meng Zhang Guodong Tan School of Electrical Engineering Anhui University of TechnologyMa’anshan243032 China

A novel DC-DC converter topology that uses a three-winding coupled inductor(TWCI)and a new voltagemultiplication technique is presented for achieving high voltage *** proposed converter comprises one boost unit,one passive absorption circuit,and two voltage-multiplier *** tertiary winding of the coupled inductor is connected to a capacitor and diode,and this combination acts as a secondary voltage-multiplier cell(SVMC).The SVMC,when combined with two capacitors,the secondary winding of the coupled inductor,a diode,and a switch,forms a primary voltage-multiplier cell,which can achieve a large voltage-conversion ratio that can be adjusted *** new voltage-multiplier technique can be used to decrease the number of capacitors and diodes,which improves the transformation efficiency.A prototype circuit with a nominal rating of 300 W is designed to verify the correctness of theoretical analysis.

关键词： Three-winding coupled inductor voltage multiplier output diode stress high step-up

Reusable electrochemical non-enzymatic glucose sensors based on Au-inlaid nanocages

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Nano Research 2022年第7期15卷 6490-6499页

作者： Lu Shen Zhen Liang Zhiyu Chen Can Wu xuefeng hu Jieyu Zhang Qing Jiang Yunbing Wang National Engineering Research Center for Biomaterials Sichuan UniversityChengdu 610065China

Mass detection of glucose,which is required in many applications,remains *** commercial enzyme-based glucose test strips cannot be reused,and current non-enzymatic glucose sensors exhibit a narrow range of detection and slow glucose oxidation ***,controlled etching of Prussian blue analogue(PBA)nanocubes at the vertices is conducted and Au nanoparticles(Au NPs)are subsequently inlaid in the etched cavities by in-situ reduction of *** unique AuNP-PBA nanocomplexes exhibit low electrochemical potential for glucose oxidation,high electrocatalytic activity,and rapid redox electron transfer *** immobilization of the Au-inlaid nanomaterials on a fine Au wire leads to a non-enzymatic glucose sensor with a particularly wide linear detection range(10μM to 16 mM),excellent anti-interference,and fast *** importantly,the sensor is reusable,and its sensitivity is well maintained even after 150 times of *** new-concept material promises to enable high-throughput glucose detection at a low cost,which is essential in diabetic management and other healthcare applications.

关键词： non-enzymatic glucose sensors Prussian blue analogues gold nanoparticles electrochemistry reusable sensors

Bioinspired integrated triboelectric electronic tongue

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Microsystems & Nanoengineering 2024年第3期10卷 97-108页

作者： Jiaming Liu Jingui Qian Murtazt Adil Yali Bi Haoyi Wu xuefeng hu Zuankai Wang Wei Zhang Anhui Province Key Laboratory of Measuring Theory and Precision Instruments School of Instrumental Science and Optoelectronics EngineeringHefei University of Technology230009 HefeiAnhuiChina School of Physics and Optoelectronic Engineering Guangdong University of Technology510006 GuangzhouGuangdongChina Department of Mechanical Engineering The Hong Kong Polytechnical UniversityHong Kong SARChina

An electronic tongue(E-tongue)comprises a series of sensors that simulate human perception of taste and embedded artificial intelligence(AI)for data analysis and *** E-tongues based on electrochemical methods suffer from a bulky size and require larger sample volumes and extra power sources,limiting their applications in in vivo medical diagnosis and analytical *** by the mechanics of the human tongue,triboelectric components have been incorporated into E-tongue platforms to overcome these *** this study,an integrated multichannel triboelectric bioinspired E-tongue(TBIET)device was developed on a single glass slide chip to improve the device’s taste classification accuracy by utilizing numerous sensory *** detection capability of the TBIET was further validated using various test samples,including representative human body,environmental,and beverage *** TBIET achieved a remarkably high classification *** instance,chemical solutions showed 100%identification accuracy,environmental samples reached 98.3%accuracy,and four typical teas demonstrated 97.0%***,the classification accuracy of NaCl solutions with five different concentrations reached 96.9%.The innovative TBIET exhibits a remarkable capacity to detect and analyze droplets with ultrahigh sensitivity to their electrical ***,it offers a high degree of reliability in accurately detecting and analyzing various liquid samples within a short *** development of a self-powered portable triboelectric E-tongue prototype is a notable advancement in the field and is one that can greatly enhance the feasibility of rapid on-site detection of liquid samples in various settings.

关键词： electronic utilizing overcome

Effect of Roucongrong(Herba Cistanches Deserticolae) decoction on the substantia nigra through Wnt/β-catenin signaling pathway in rats with Parkinson's disease induced by 6-hydroxydopamine hydrochloride

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Journal of Traditional Chinese Medicine 2021年第5期41卷 762-770页

作者： XU Qian QIN Wei WU Fangzhen LIN Yao HONG Liting CHEN Dan hu xuefeng CAI Jing Fujian Key Laboratory of Developmental and Neural Biology College of Life ScienceFujian Normal UniversityFuzhou 350117China College of Integrative Medicine Fujian University of Traditional Chinese MedicineFuzhou 350122China Department of Rheumatology and Endocrinology The Second Affiliated Hospital of Fujian Traditional Chinese Medical UniversityFuzhou 350003China Institute of Pharmacy Fujian University of Traditional Chinese MedicineFuzhou 350122China

OBJECTIVE:To investigate the effect of Roucongrong(Herba Cistanches Deserticolae)decoction on the substantia nigra in rats with Parkinson’s disease(PD)induced by 6-hydroxydopamine hydrochloride(6-OHDA).To further determine whether the Wnt/β-catenin signaling pathway is involved in the ***:A rat model of PD was established by intracranial injection of ***,three concentrations of Roucongrong(Herba Cistanches Deserticolae)decoction were prepared and administered to rats by gavage therapy for 14 *** changes were measured in PD *** vivo tyrosine hydroxylase(TH)levels in the substantia nigra were examined by ***,gene and protein expression levels of members of the Wnt/β-catenin signaling pathway were examined by Western blotting and polymerase chain ***,a Wnt/β-catenin inhibitor was used to investigate the mechanism of action in 1-methyl-4-phenylpyridinium(MPP+)-treated MES23.5 cells in ***:Roucongrong(Herba Cistanches Deserticolae)decoction improved performance in the stride and gait adjustment tests in PD *** also increased TH in the substantia nigra and altered the expression of genes and proteins in the Wnt/β-catenin signaling ***/β-catenin inhibitor reduced the effect of Roucongrong(Herba Cistanches Deserticolae)decoction in MPP+-treated MES23.5 ***:Roucongrong(Herba Cistanches Deserticolae)decoction may promote neuronal survival in PD in vivo and in vitro by increasing TH content in the substantia nigra and by activating the Wnt/β-catenin signaling pathway.

关键词： Cistanche Parkinson disease survival tyrosine 3-monooxygenase Wnt signaling pathway